Interactive two-way pagers and a pager network system in support thereof are known. Examples of such two-way pagers include the RESEARCH IN MOTION (RIM) “BLACKBERRY” two-way pager designed and/or marketed by RESEARCH IN MOTION Limited of Waterloo, Ontario, Canada and the MOTOROLA two-way pager designed and/or marketed by MOTOROLA Corporation of Schaumberg, Ill., USA. Such pagers typically include a battery compartment for receiving a battery, a processor, memory, a data screen for displaying alpha-numeric data, a micro-size keyboard for entering alpha-numeric data, a radio receiver for receiving data over air, and a radio transmitter for transmitting data over air. Accordingly, data may be transmitted from one pager and received by another by way of the network system. Likewise, data from a source external to the network system may be received by a pager, and such pager may transmit data to a destination external to the network system. In addition, such pagers typically include a serial port or the like by which data may be uploaded and/or downloaded, for example during pager initialization, set-up, and upgrade at a pager sales and/or service center.
Examples of pager network systems include the MOBITEX network designed and/or marketed by ERICSSON MOBILE COMMUNICATIONS AB of Sweden and the REFLEX network designed and/or marketed by MOTOROLA Corporation of Schaumberg, Ill., USA. Such network systems (“networks”) typically include one or more base stations, where each base station has associated with it a plurality of geographically spaced base transmitters, each of which can potentially transmit the data received by the radio receiver of the pager, and a plurality of geographically spaced base receivers, each of which can potentially receive the data transmitted by the radio transmitter of the pager. The base transmitters and the base receivers are spread out over a network coverage area, and each is assigned particular transmitting or receiving frequencies by its respective base station.
As should be appreciated, each base station is responsible for directing pager data to its ultimate destination or from its ultimate source. Such base station also assigns the frequencies to the base transmitters and base receivers, keeps track of the locations of pagers with respect to base transmitters and base receivers, assigns each pager to a particular base transmitter and to a particular base receiver as the pager is moved through the network coverage area, or at least through the portion thereof that the base station is responsible for, and transmits information to each pager regarding the assigned base transmitter and assigned base receiver and/or frequencies thereof, among other things. Since the pager must acknowledge receipt for data verification purposes and the like, among other things, the pager must always be in two-way communication with the network, even if only receiving data from such network.
Typically, the base transmitters operate at a relatively high power, owing to the fact that each pager is battery-operated and the receiver therein operates at a relatively low power. Also owing to the fact that each pager is battery-powered and the transmitter therein likewise operates at a relatively low power, the base receivers are typically concentrated at a higher number per geographical area than the transmitter base stations in the network coverage area. Accordingly, it is statistically more likely that a pager is closer to a base receiver than to a base transmitter. Correspondingly, it is also more likely that a pager in a fringe (i.e., area on the edge) or marginal (i.e., an area with poor transmission quality) portion of the network coverage area can receive data from a base transmitter, but that a base receiver cannot receive data from such pager, owing to the relatively low transmitting power of such pager.
The network coverage area for a pager network is typically finite. For example, such network coverage area may roughly correspond to a state or region, a portion of a state or region, a metropolitan area, a metropolitan area extending over portions of several states or regions, or the like. Accordingly, through cooperative service agreements between networks, ‘roaming’ pager coverage may be provided for a pager outside the network coverage area of its ‘home’ network. With such cooperative service agreements, the over-all pager coverage area encompasses a large portion of urban areas in the United States, and many rural areas too. Inevitably, though, there are significant portions of the United States where pager coverage is not available. As should be appreciated, coverage for a pager is not available anywhere the pager cannot communicate with both a base receiver and a base transmitter to achieve the aforementioned two-way communications link. For example, coverage is not available in fringe or marginal portions of the network coverage area or the over-all pager coverage areas (if roaming coverage is provided), as was pointed out above, and in areas external to the network coverage area or the over-all pager coverage areas (if roaming coverage is provided). This is true even if the pager can communicate with a base transmitter. Of course, coverage will also not be available anywhere the pager cannot communicate with a base transmitter, but for the reasons specified above, it is more likely that loss of communication with any base receiver will occur first, or at least concurrently.
Equally inevitably, individuals with two-way pagers or the like visit areas where coverage is not available, both in and out of the United States, and such individuals would like some sort of continued two-way paging service even though in such areas without coverage. Accordingly, a need exists for a method and apparatus to provide coverage for a two-way pager or the like, especially when the pager is outside the aforementioned coverage area